A usual slide fastener engages a pair of element rows when a slider is moved forward. However, while the slider is moved forward, a cloth may be jammed in a slider body.
Therefore, a slider configured to make it difficult for the cloth to be jammed in the slider body has been known. For example, as an example of the conventional slider, a slider has been known in which a slider body is formed by front and back plates arranged to face each other, a central member configured to connect the front and back plates and side plates protruding from right and left sides of the front and back plates and a surface (front surface) of the slider body facing toward an engaging direction is configured as a concave surface (Patent Document 1). When the slider is moved in the engaging direction, even though the cloth is between (inside) the pair of element rows, the cloth is guided toward a bottom-side of the concave surface as the slider is moved and finally passes under the slider. In this way, the slider prevents jamming of the cloth.
Also, as an example of a slide cover to be mounted to the slider, a slide cover has been known which has upper and lower plates arranged to face each other in an upper-lower direction, a connection post configured to connect the upper plate and the lower plate, an accommodation portion provided in the upper plate and configured to accommodate therein an upper blade of the slider and a pair of element passages provided at right and left sides of the connection post (Patent Document 2). At an entry edge portion of the element passage, an angle between front surfaces of the upper and lower plates and an axis line (an extension direction of the passage) of the element passage is set within a predetermined range, so that the slide cover is difficult to jam the cloth therein. Further, in FIGS. 6 and 8 of Patent Document 2, the front surfaces of the upper and lower plates are configured as convex surfaces each of which has an opposite shape to the front plate of Patent Document 1, i.e., an inverted V shape. Therefore, when the slider is moved in the engaging direction, the cloth located at the engaging direction-side of the slide cover moves along the convex surfaces as the slider moves and divides to the right and left sides of the slide cover. In this way, the slider prevents the jamming of the cloth.